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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').

10044 results found.

  1. GRB 030227: Optical observations
  2. IPN triangulation of GRB030301 (annulus)
  3. 030302: NOT A GRB
  4. 030228: NOT A GRB
  5. GRB 030226: R band polarimetric observations
  6. GRB 20030226: Upper limits from recent and historical observations
  7. GRB030227 - faint tentative OT candidate
  8. XMM-Newton observation of GRB030227
  9. GRB030226: ESI spectroscopy
  10. GRB030226 (=U10893): A Long GRB Localized by the HETE WXM and SXC
  11. GRB030226: optical observations and refined redshift
  12. GRB 030226 Optical Spectra and R,I,z' Imaging
  13. GRB030226: Candidate optical afterglow
  14. IPN triangulation of GRB030220 (annulus)
  15. IPN triangulation of GRB030217 (small error box)
  16. IPN triangulation of GRB030215C (annulus)
  17. IPN triangulation of GRB030217 (annulus)
  18. IPN triangulation of GRB030215A and GRB030215B (annuli)
  19. IPN triangulation of GRB030204 (small error box)
  20. IPN triangulation of GRB030127 (annulus)
  21. GRB 030115: Further IR observations with IRSF/SIRIUS
  22. GRB 030115: IR observations with IRSF/SIRIUS
  23. GRB030115: R-band counterpart of IR candidate
  24. GRB 021211: R-band observations at late-time
  25. IPN triangulation of GRB030115B (small error box)
  26. GRB030115 (=H2533): A Long GRB Localized by the HETE WXM and SXC
  27. IPN triangulation of GRB030115B (annulus)
  28. GRB030115: R-band observations at Asiago
  29. IPN triangulation of GRB030101 (two large error boxes)
  30. Probable GRB in INTEGRAL SPI-ACS
  31. GRB021219, optical observations
  32. IPN triangulation of GRB021214 (annulus)
  33. GRB 021211, optical observations
  34. GRB 021211, optical observations
  35. GRB021211 - Upper limits from recent and historical observations
  36. GRB021211 (=H2493): A Bright, Long GRB Localized by HETE-2 in Near-Real Time
  37. HETE 2493: Optical observations
  38. IPN triangulation of GRB021201 (short/hard burst, small error box)
  39. GRB021125 refined position
  40. IPN triangulation of GRB021125B (two large error boxes)
  41. GRB021113, SPI ACS observation
  42. GRB021113: optical observations at Bisei
  43. GRB021112: Optical Observations
  44. IPN triangulation of GRB021113 (=H2449; annulus)
  45. GRB021113 (=H2449): A Long GRB Localized by HETE
  46. GRB021112 (=H2448): A Long GRB Localized by HETE
  47. IPN triangulation of GRB021104 (annulus)
  48. GRB021104(=H2434): A Long, X-Ray-Rich GRB Localized by HETE
  49. IPN triangulation of bursts from SGR1900+14, November 1-2, 2002
  50. GRB021104: Candidate present in DSS
  51. IPN triangulation of GRB021025 (portion of annulus)
  52. IPN triangulation of GRB021025 (annulus)
  53. IPN triangulation of GRB021023 (small error boc)
  54. IPN triangulation of GRB021020 (smaller error box)
  55. GRB021021(=XRF 021021): An X-ray Flash Localized by HETE
  56. IPN triangulation of GRB021020
  57. GRB 021004: VRI observations at TNG: possible break
  58. GRB021016(=H2397): A Long GRB Localized by HETE
  59. IPN triangulation of GRB021016 (small error box)
  60. IPN triangulation of GRB021014 (large error box)
  61. GRB021004: High-resolution optical spectroscopy
  62. GRB 021004: Optical/NIR Observations
  63. GRB 021004: Additional V-band Polarimetric Observations
  64. GRB021004: optical observation
  65. GRB 021004: WC wind?
  66. IPN triangulation of GRB021007 (annulus)
  67. XRF 020903 spectrum
  68. GRB021004: optical observations and predicted break time
  69. GRB021004: restart of optical decay
  70. GRB 021004: Optical Decay
  71. HETE fluences for GRB021004
  72. GRB 021004: V-band Polarimetric Observations
  73. GRB021004: Update Bisei photometric data
  74. GRB 021004: Optical Decay
  75. GRB021004, Optical Observations
  76. GRB021004: Upper limits from recent and historical observations
  77. GRB021004(=H2380): Revised Localization with HETE Soft X-ray
  78. GRB021004(=H2380): A Long GRB Localized by HETE in Near-Real Time
  79. XRF020903: TNG and Asiago photometry
  80. XRF 020903: Correction to GCN 1560
  81. XRF 020903: VRI observations
  82. XRF 020903: Supernova
  83. Single IPN error box for GRB020904
  84. IPN triangulation of GRB020904
  85. GRB020903(=H2314): An X-Ray Flash Localized by HETE
  86. GRB020819(=H2275): Revised Localization with HETE Soft X-ray
  87. SGR1900+14 burst localized by HETE
  88. GRB020813: High-resolution optical spectroscopy
  89. Second epoch K band imaging of GRB 020819
  90. K band observation of GRB 020819
  91. GRB020819(=H2275): A Long Burst Localized by the HETE WXM and SXC
  92. IPN triangulation of GRB020819 (HETE 2275)
  93. GRB 020813: addendum to GCN 1498
  94. GRB020813: V-band decay slope
  95. Polarimetry of GRB020813: evidence for variability
  96. GRB020813: High-Resolution Optical Observations
  97. GRB020813(=H2262): Revised Localization with HETE SXC
  98. GRB020813, optical observations
  99. IPN error box for GRB020813
  100. IPN triangulation of GRB020813

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